Medicine and Health Sciences Commons^™

Effect Of Amputation On Muscle Structure Properties In A Rabbit Model, Roy Caleb Stubbs

Masters Theses

After amputation, muscles in the residual limb are detached from their insertion points and no longer span the missing joints. Our objective was to quantify the effect of amputation-induced disuse on residual muscle structure, an indirect indicator of muscle force-generating capacity. One hind paw was surgically removed at the ankle joint of ten rabbits. At two weeks (n=5) and 4 weeks (n=5) post-amputation and for select muscles (gastrocnemius, soleus, tibialis cranialis, extensor digitorum, and flexor digitorum superficialis), we measured and computed several muscle structure properties. Additionally, we qualitatively assessed the muscle fiber appearance of histological samples at each timepoint. At …

The Effects Of Footwear Longitudinal Bending Stiffness On The Energetics And Biomechanics Of Uphill Running, Justin Angelo Ortega

Masters Theses

There has been a prevalence of long-distance running footwear incorporating carbon-fiber plates within their midsoles, effectively increasing their longitudinal bending stiffness (LBS). This modification of modern racing footwear has occurred concurrently with large improvements in running times (Bermon et al., 2021), putting into question how these footwear components affect performance (Muniz-Pardos et al., 2021). The current literature has investigated this at level running, but with the increasing popularity of trail running, it is of interest to investigate whether the benefits found during level running translate to graded running. Therefore, the overall aim of this study was to investigate the effects …

Therapeutic Intervention Or Rider Influence On The Electromyographic Activity And Kinematics Of Horses, Karen L. Shaw

Masters Theses

Core strengthening and postural stability are desired outcomes of certain therapeutic exercises performed in horses. This study aimed to quantify changes in muscle activation at a walk and trot in horses traveling over eight consecutive ground poles evenly spaced (at 30 inches for walk and 48 inches for trot) in parallel fashion in a straight line, and with hindquarter and abdominal elastic resistance bands applied at 25% stretch. Surface electromyography (sEMG) data were collected for the longissimus dorsi and rectus abdominus muscles in six horses. A 2x2 repeated measures ANOVA was performed for each muscle to test for significant differences …

Visuomotor Adaptation During Asymmetric Walking, Charles Napoli

Masters Theses

Necessary for effective ambulation, head stability affords optimal conditions for the perception of visual information during dynamic tasks. This maintenance of head-in-space equilibrium is achieved, in part, by the attenuation of the high frequency impact shock resulting from ground contact. While a great deal of experimentation has been done on the matter during steady state locomotion, little is known about how head stability or dynamic visual acuity is maintained during asymmetric walking.

In this study, fifteen participants were instructed to walk on a split-belt treadmill for ten minutes while verbally reporting the orientation of a randomized Landolt-C optotype that was …

Impact Of Parity On Gait Biomechanics, Bekah P. Stein

Masters Theses

Background: Symptomatic knee osteoarthritis (OA) is an incurable condition that affects nearly 50% of adults, and women are twice as likely as men to develop OA. Throughout pregnancy, women experience large changes in morphology and gait mechanics, as well as changes in joint loading. It is possible these adaptations could cause lasting changes postpartum, which may potentially contribute to initiation of OA, thereby increasing the overall risk of OA for women.

Purpose: This exploratory study looked to identify differences between lower limb gait mechanics of healthy nulliparous women and healthy parous women.

Methods: 28 healthy female participants (14 parous, 14 …

Kinematic Analysis Of Trunk Coordination Throughout The Rowing Stroke Sequence, Mcdaragh Rose Minnock

Masters Theses

Rowing at the elite level requires proper sequencing of the rowing stroke so that the rower is able to produce an efficient stroke while protecting oneself from potential injuries. The cyclic motion of the rowing stroke sequence at low loads often results in overuse injuries, specifically in the lower back. Kinematic data of rower’s pelvis-lumbar-thoracic spine were collected using inertial measurement sensors. An incremental step-test was conducted to observe the influence of increasing intensities on the lumbar-pelvis and lumbar-thoracic segments coordination and coordination variability. This study provides a new way of quantifying rowing kinematics using vector coding. The vector coding …

Gait Changes During Exhaustive Running, Nathaniel I. Smith

Masters Theses

Runners adopt altered gait patterns as they fatigue which may increase energy expenditure and susceptibility to certain overuse injuries. Previous investigations have described changes in muscle performance and kinematic gait variables resulting from running fatigue. The purpose of this investigation was to characterize changes in joint moment patterns that develop as runners fatigue in order to better understand the kinetic bases for kinematic fatigue effects. It was hypothesized that when fatigued, runners would demonstrate increases in stance time, peak stance phase knee flexion angle, peak knee extension moment, peak swing phase hip flexion moment, and hip extension and plantarflexion angular …

Does Footfall Pattern In Forefoot Runners Change Over A Prolonged Run?, Carl W. Jewell

Masters Theses

There has been much debate on the benefits of a forefoot versus rearfoot strike pattern in distance running in terms of performance and injury prevalence. Shock attenuation occurs more prominently in soft tissues at impact in forefoot runners compared to the passive skeletal loading in rearfoot runners. Recent studies indicate that a forefoot strike pattern may not be maintainable over long distance efforts. Therefore, this study tested the hypothesis that habitual forefoot runners could not maintain their strike pattern throughout a prolonged, intensive run.

Fourteen forefoot runners ran to voluntary exhaustion on an instrumented force treadmill (average run duration: 15.4±2.2 …

Kinetic Asymmetries During Submaximal And Maximal Speed Running, Devon H. Frayne

Masters Theses

An important issue for sports scientists, coaches and athletes is an understanding of the factors within a running stride that can enhance or limit maximal running speed. Previous research has identified many sprint-related parameters as potential kinetic limiters of maximal Center of Mass velocity (Chapman and Caldwell, 1983b; Weyand et al., 2001). Bilateral asymmetry is present for many of these parameters during running; however the degree to which such asymmetries change as running speed increases is unknown. It was hypothesized that asymmetries in key sprinting parameters would be larger at maximal speed than all other tested speeds. Kinematics and kinetics …

Biomechanical Differences Of Two Common Football Movement Tasks In Studded And Non-Studded Shoe Conditions On Infilled Synthetic Turf, Elizabeth Anne Brock

Masters Theses

The purpose of this study was to examine kinematic and kinetic differences in three shoe conditions (traditional football shoes with natural and synthetic turf studs and a neutral running shoe) during two common football movements (a 180° cut and a land-cut movement) on infilled synthetic turf. Fourteen recreational male football players performed five trials in all three shoe conditions for a 180° cut as well as a land-cut maneuver. The kinematic and kinetic variables were analyzed with a 3 x 2 (shoe x movement) repeated measures analysis of variance (ANOVA, p<0.05). Peak free moment was significantly greater for the land-cut trials (p<0.001). Vertical GRFs were significantly greater for the land-cut trials (p<0.001). A cleat x movement interaction was seen for time to vertical impact GRF (p=0.048). A cleat main effect was found for time to vertical impact between natural turf cleat and synthetic turf cleat (p=0.019). Vertical loading rate was significantly greater in land-cut trials. Peak medial GRFs showed a significant cleat x movement interaction (p=0.002). The results from this study suggest that land-cut movement elicit greater vertical GRF and vertical impact loadings rates. The running shoe had significantly less dorsiflexion range of motion (ROM) than the synthetic turf studs. A significant cleat main effect was found for peak eversion velocity (p=0.005). Post hoc comparisons showed that it was significantly smaller in shoe than that natural turf stud (p=0.016) and synthetic turf stud (p=0.002). In general, there was a lack of differences between the shoe conditions for GRFs and kinematic variables. For the 180° cut movement, natural turf studs produced lowest peak medial GRF compared to the synthetic turf studs and the shoe. The results from this study suggest that land-cut movement elicit greater vertical GRF and vertical impact loadings rates. In general, there was a lack of differences of GRFs and kinematic variables between the shoe conditions. For the 180° cut movement, natural turf studs produced lowest peak medial GRF compared to the synthetic turf studs and the shoe. Overall, increased GRFs, especially in combination with rapid change of direction and deceleration may increase the chance of injury.